A man has explained how his life was turned upside down when he discovered that his wife is, in fact, his half-sister.

In a lengthy Reddit post, the man clarified that he was adopted two minutes after he was born and has never known anything about his biological parents. He also said he met his wife “by chance” eight years ago.

He said that they have two children together, a girl of four and a two-year-old boy, and that his wife “got sick just after our son was born and now is in need of a kidney transplant”.

He claimed that none of her relatives was a match or viable doner, so he got tested to see if he could fulfill the life-saving role.

“I got a call the other day saying that I was a match,” he wrote. “The doctor then said something about wanting to do additional testing due to some information from the HLA (human leukocyte antigen) tissue test results. I didn't think much of it and agreed.”

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The results then came in and the bombshell hit.

“[The doctor] explained that because of how DNA information is passed down through generations a parent to a child could have at least a 50 per cent match,” he recounted. “Siblings could have a 0-100% match. It was rare to have a high match as husband and wife.”

However, the man and his wife were found to have an abnormally high match percentage.

“Shocked and confused” he then asked the doctor what that all meant.

“Long story short [we’re] related,” he said.

The Redditor went on: “No I'm not kidding. I was put up for adoption before I was born. Placed into a family that moved across the country. I knew I was adopted but we didn't have any information about my bio family. It was a closed adoption.

Wrapping up his jaw-dropping revelation, he concluded: “I don't know what [to] do moving forward but I know it may be wrong. She is my wife and the mother of our kids.”

The post racked up more than 27,500 up-votes in a month on the TIFU Subreddit, as fellow users attempted to make sense of the original poster (OP)’s predicament.

“I mean, at this point, you are married with children already – can’t take that back so don’t see much point in blowing worlds up I guess,” one wrote.

Another argued: “People have a kneejerk reaction because [of the term] ‘incest’ but the major reason why incest is f**king weird and wrong is the social/family relationship aspect of it.

“In OP's case, he literally has never known his wife as a family member so there's nothing taboo about it.”

They continued: “The actual reason for concern by OP is the chance of passing on bad genes/traits that both you and your partner have, but those effects usually need multiple generations to compound in any statistically meaningful way, I think?

“If all OP's children are perfectly healthy, it's probably completely safe to have more kids who will also turn out completely fine.”

However, another recommended: “Probably wise to consult a medical professional before having any further kids though; just to be safe.

They added: I hope OP isn't too shook [sic]. It's a really peculiar situation but there's no shame in this. Even if the current kids aren't as healthy as they otherwise could be. It's no one's fault.”

In an update shared two weeks after his original post, the OP offered more details on the situation and confirmed that he hadn’t yet told his wife about the unwelcome discovery.

“My children are fine. My daughter is incredibly smart for her age. My son is a handful and healthy,” he said.

He went on to explain that his wife hadn’t been present when the doctor went through the test’s findings with him, but added that the results “confirm one of my bio parents is one of hers”.

“t can also mean first cousins or aunt/uncle – I'm guessing her dad,” he added.

He went on: “I'm not going to bring this up ever. I might look at my FIL (father-in-law) differently but nothing will hopefully change. I hope none of the family goes on Reddit and connects the dots.”

Ending his statement, he said: “I am donating my kidney to my wife. We have started the full process. That takes time and a lot of preparation. I plan on talking to my wife after the surgery and after recovery. We will decide what to do with our kids. If we are going to get them tested or ever tell them.

“I will not be leaving my wife. I love and will always be there for her. I made vows and I will keep them. I love her more than I would a half-sister.”

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